VIERA, Fla. -- There are high expectations for the Washington Nationals this year in the National League East, both externally and within the organization. Typically, these types of contending teams look to acquire big league talent to help put that championship puzzle together.

The offseason trade the Nationals made, sending lefty prospect Robbie Ray to the Tigers for Doug Fister made perfect sense. Bringing in veteran catcher Jose Lobaton by dealing pitching prospect Nathan Karns to the Rays also seemed to fit. What was off script, however, was getting two prospects in return from Tampa Bay as well, both of whom are on Washington's new Top 20 Prospects list.

"Not only were we able to get a player in Lobaton we feel good about, at the same time we were able to replenish the system to a degree with Felipe Rivero and Drew Vettleson, who are very interesting guys," Nats farm director Doug Harris said. "Robbie Ray, we really valued his talents, but maybe Rivero slides into that hole a little bit. You gain some years of youth vs. Karns in the deal. And we get an outfield prospect we're excited about."

The Nationals are most fired up about the guy at the top of the list, understandably. Lucas Giolito, the organization's top pick in the 2012 Draft, is preparing to get his professional career really going in 2014. The top high school arm in that class, Giolito had Tommy John surgery at the end of that summer, missing nearly all of the 2013 campaign. He'll have limits on his innings and pitches, within a given outing, but fans of the South Atlantic League should get ready to see the big right-hander in action.

"We're excited about him going out and competing for a full season, getting him through five months," Harris said. "His talent has been well-discussed. For us, it's just him continuing to learn the process for every fifth day, build that routine and get the feeling what it's like to compete with 24 other men over the course of a championship season."

While Giolito and A.J. Cole are the only members from the Nats' system on the Top 100 Prospects list, Harris is fairly pleased with where the organization is currently. The big league roster might be fairly set right now, but there's a group of talent amassing at the upper levels, ready to be called upon when there's a need, and there's another wave getting ready to push up behind them.

"There are the players who either had the chance to play in the big leagues briefly or are on the verge of that, and we have more volume with them this year," Harris said. "Then we have a group of younger kids who have some ceiling to them that we're really excited about. As a whole, we feel really good about where the system is right now."

Left-hander Sammy Solis was a second-round pick of the Nationals in the 2010 Draft and has missed considerable time due to injuries.

MLBPipeline.com: This is a different spring for you, now that you are fully healthy. What has your mindset been like?

Solis: The arm hasn't been a factor at all. I'm just coming out here and working hard. That's all I can do, not stress, not force anything, because the decisions aren't up to me. I'm coming out here like just another guy, working hard, and we'll see what happens. I would say I like this a lot more, trying to prove my skill rather than just get healthy. I think it's nice to be out here and be 100 percent, not worrying about anything other than going out there and getting the ball in the strike zone.

MLBPipeline.com: If things go well and you throw the ball the way you're capable of, you could have a chance to help out in Washington in the near future. Is that something you keep in the back of your mind, or do you not? Is it fun to go out and try to compete like that?

Solis: I think it's both. If you base your play off of "Am I going to make the next cut?" things aren't going to happen. I'm going out there every day throwing like I know I can and let the decisions be made by skipper or the front office. I think it's both ways. I want to think about it. At the same time, you don't at all.

MLBPipeline.com: There are a lot of expectations for the big league team. How does that trickle down to guys fighting for jobs, or for guys who will be in Double-A or Triple-A, that if you do get up, there are expectations of success?

Solis: I'd rather that there be high expectations than no expectations. I think it's exciting having a team that's competitive and able to possibly win a World Series. Possibly having the chance to be a part of that is more exciting than if we were some other team that wasn't contending.

Souza was not on the Nationals' Top 20 list a year ago. That's not surprising, given that he was entering his sixth season with the organization since being a third-round pick in the 2007 Draft out of the Washington high school ranks and had yet to get out of A ball.

Things finally started to click in 2013 with a move to Double-A, where he continued to refine his approach at the plate while showing some power and baserunning acumen. A solid Arizona Fall League campaign led to his addition to the 40-man roster and an invite to big league camp. And he's now No. 14 on that Top 20.

Though he certainly got off to a good start, going 5-for-10 with a pair of doubles in his first taste of Grapefruit League action, it's more about how he's acted and gone about his business than anything production-wise.

"It's his first Major League camp and he's gone about his work with a great deal of maturity, a great deal of detail," Harris said. "He hasn't wavered from his approach one iota, even though he has an opportunity to show people some of the power potential he possesses."

Souza has hit as many as 23 home runs in a season, doing that in just 97 games in 2012. Over the past two seasons, he's cut down on his strikeouts, continued to draw walks and hit for a higher average. That's exactly what the Nats' brass has seen from him this spring.

"He's really continued to be disciplined with his approach, line drive after line drive, alley to alley," Harris said. "We know there's power in there, but he hasn't wavered from his approach. I really tip my cap to him in his first camp."

Breakout candidate: Solis

Ever since coming out of the University of San Diego in 2010, Solis has shown just how effective he can be on the mound. The only problem has been keeping him there for extended periods of time.

The big left-hander has yet to throw more than 100 innings in one season. Solis has the potential to be a very efficient starter, one who rarely issues walks and has the three-pitch mix to succeed at the highest level. With his arm issues now seemingly in the rearview mirror, he has the chance to fulfill his potential and have a huge 2014, perhaps even helping out in Washington at some point.

"It's not out of the question," Harris said. "His stuff we've seen in short spurts certainly has the opportunity to play at that level. When you look up at the end of the year, I think we're all going to be thrilled with where he is and what he's done."

Jonathan Mayo is a reporter for MLB.com and writes a blog, B3. Follow @JonathanMayoB3 on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.